Effects of ceria/zirconia ratio on properties of mixed CeO2-ZrO2-Al2O3 compound

Abstract A series of Ce x Zr 0.50− x Al 0.50 O 1.75 (0.05≤ x ≤0.45) mixed oxides with different Ce/Zr ratio were prepared by co-precipitation method and characterized by means of X-ray diffraction (XRD), Brunauer-Emmet Teller method (BET), temperature-programmed reduction (H 2 -TPR) and oxygen pulsing technique. The XRD results showed that all samples kept the single CeO 2 cubic fluorite structure after calcination at 600 and 1000 °C for 5 h. The results of BET revealed that Ce x Zr 0.50− x Al 0.50 O 1.75 with Ce/Zr molar ratio 1/1 exhibited higher specific surface area (212 m 2 /g) and larger pore volume (0.40 ml/g). For all aged samples, CZA with Ce/Zr molar ratio 3/7 presented the highest specific surface area (104 m 2 /g) and pore volume (0.34 ml/g). The compounds could still keep prominent structural and textural stability with excellent redox properties even calcined at 1000 °C.